For premium accounts (including the trial), our tracking code sends "pings" while a visitor sits on a single page. By default, after 10 minutes, the pinging stops. So visitors with only a single page view who had your website open for 10 or more minutes will be reported as being there for exactly 10 minutes, +/- a few seconds potentially.

Pinging can be extended up to 4 hours by following the instructons on the customized tracking page.